This article has been cited by other articles in PMC. It may be one or a combination of low sperm concentration, poor sperm motility, or abnormal morphology.
During sperm maturation, chromatin undergoes an extensive compaction through the progressive replacement of histones with basic, positively-charged proteins called protamines. Interestingly, in human and other It has been suggested that preserved nucleosomes have a role in promoting transcription after fertilization, however their localization and function is still a matter of debate.
The aim of the present work was to understand if the localization of histones in human sperm DNA is affected Infertility research papers genome composition, a feature linked to several biological functions. In order to do that, we mapped histone-enriched sequences along isochores, which are large chromosomal territories characterized by fairly homogeneous guanine and cytosine GC composition.
We retrieved publicly available human sequences found to be histone-enriched in sperm chromatin and localized them along isochores by using their respective coordinates. We found that the majority of genes and sequences associated with mononucleosomes, the activating chromatin mark H3K4me3 and the repressive mark H3K27me3 reside in the GC-poor isochores.
Genes harboring the activating mark H3K4me2, instead, are preferentially located in the GC-rich isochores. For genes carrying histones with specific marks, we speculate that developmental and tissue-specific genes carrying the H3K27me3 mark might take advantage by residing in GC-poor isochores because in these regions they can be shut off immediately after the end of their transcription more easily than in GC-rich isochores.
On the contrary, housekeeping genes marked with H3K4me2 would not need this kind of regulation and reside in GC-rich isochores. For other genes and sequences, further analyses are required in order to clarify the role of GC composition in histone retention in sperm chromatin. In conclusion, although the complete scenario of sperm chromatin has not been elucidated yet, correlations seem to exist between chromatin modification patterns, isochore structure and gene expression timing in embryo development.Infertility Research Paper This sample Infertility Research Paper is published for educational and informational purposes only.
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A medical research paper may take a holistic approach to examining the phenomenon of infertility, focusing on both the physical and emotional ramifications of the condition. Jun 15, · Supported research also includes studies of the short- and long-term consequences of infertility or infertility-associated treatments and the psychological processes that occur during infertility experiences and treatment.
"Infertility" Essays and Research Papers. Infertility Infertility Infertility Research Paper. What is infertility? Infertility is defined as inability to conceive despite have regular unprotected intercourse for at least 12 months or for at least six months for a woman over the age of Research Papers on Infertility Infertility Research Papers examine this phenomenon and focuses on the physical and emotional ramifications of this condition.
Research papers on infertility can discuss many aspects of the issue that causes women and men a grave amount of anxiety and concern.
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